Rotary pump or motor



Dec. 24,. 1940. R. J. SMITH 2,225,803 ROTARY PUMP 0R MOTOR Filed Nov. 28, 1938 Patented Dec. 24, 1940 UNITED STATES PATENT OFFICE ROTARY PUMP OR, MOTOR Ralph John Smith, Monkseaton, England, assignor to William Armstrong Woodeson, Newcastleon-Tyne, England; Reginald Claude Roe, Rochdale, Lancaster, England; Ralph John Smith, Monkseaton, England; and Clarke, Chapman & Company Limited, Gateshead-on-Tyne, Durham, England Application November 28, 1938, Serial No. 242,822

Y In Great Britain June 29, 1938 1 7 Claims. (Cl. 103-120) This invention relates to rotary fluid pumps of the vanes from the rotor does not of itself and motors (hereinafter for convenience referred afiect the volumetric discharge of the pump. to as pumps) of the type in which vanes move in The radial movements of the vanes are effected slots in the rotor while the stator or casing is of by p and rollers thereon at pp n 5 two different radii with the inlet and outlet (sides) of each v ne wh h e i m r ve r 5 branches at the points where change of radius slots formed in the end covers of the casing or occurs and in which the fluid has access to the in p s Sp o e o Sa d end covers- The vane underside of the vane. tips are, by said pins, roller and cam grooves, I The principal object of the present invention held in contact with the wall of the casing bore.

stant speed of driv infinit variat may b b. rollers when these move inward or outward, suittained in the pumping papacity of th pump, able connecting ports are provided for coupling Another object of the invention is to better w ja n sp wh n m ving inward or outimpart the required movements to. the vanes to Ward, 011 e delivery inlet Side Of the p- 1 cause them to follow the contour of the casing The i v n ion will be best understood from and th ab tm nt hi h forms t part of th further description with reference to the accomcasing of red d i panying drawing, wherein Fig. 1 is a transverse A further object of the invention is to ensure Section through 0118 constructional form P p that projection of the vanes from the rotor does according to the nvention, with the rotor in 2 not of itself cause any variation in the volumaximum delivery P s metric capacity of th pump, Fig. 2 is a part sectional view at right angles The invention is also directed to further ensurto 1 P011101} of the Pump? m smooth running f the pump under all Fig. 3 is a face view of an element not fully ditions of volumetric discharge. Seen in 1; Fig. 4 1s a plan view of other elements of Fig. 2

In accordance with this invention I provide or so arrange that the casing or stator can be adjusted relatively to the rotor, or vice versa, so as to bring their axes into and out of coincidence and thus to vary the volumetric discharge of the pump between zero and full capacity. The adjustment, which may be effected by any suitisolated from the remainder for the sake of clarity; and

Fig. 5 is a view similar to Fig. 1 of part of the pump showing the rotor in or about the position of no delivery." 30

As shown in said drawing, the pump comprises a main or outer casing I with an inlet 2 able known means is made in dlrection at and an outlet 3 in line with each other, the

right angles to the axis which extends between m 1 the inlet and outlet branches of the pump. .The igggifi z z f -5 posmon of majximum delivery capacity. is secured latter is journalled in the casing I for driving in when the casing and rotor are co-axial, so that any usual or suitable way. Denommated by the the rotor periphery comes against the portion of numeral 6 is the central portion of an inner the casing of reduced radius. The position of zero casing or pump stator which is bored cylindrical dew/er? is secured when the rotor periphery 1S td a diameter larger than that of the rotor body approxlmately fxlui'distant between the parts of 4, while I is a landing block curved interiorly to the casing dlfierent radius P the amount fit the body 4 and exteriorly to fit the bore in the of fluid earned between the pump inlet and outstator portion 5' thus formin the pump chamber l t is qu t at a ri d between t pump of different radii as stated hereinbefore.

let and inlet, so that no external discharge oc- The said inner casing or t t 5 is completed 45 6113- by a pair of side plates 8 (Figs. 2 and 3), each The number of vanes can be any ir odd formed with a cam track 9 for rollers I0 which number. d numbers being necessary to project from the. sides or ends of vanes ll sure the fluctuations in volumetric p i ada ted to slide radially in slots I! in the rotor caused when pump is running at less than maxibody, the arrangement being such that the vanes mum output, being matched out. The vanes and remain stationary in their slots while travelling the slots in the rotor are also cut away at the circularly along or across the face of the landleading side of the vanes so that fluid can enter ing block 1 and also while travelling along a the slots and get beneath the vanes, the effect of similar region of the bore in the stator opposite this being that the varying extent of projection thereto, as will be apparent from Fig. l. The 55 is to effect improvements whereby with a con- To a id t pp g f t fl d tw dja nt stator is capable of being displaced, in this instance raised and lowered,by turning a hand wheel l2a fitted to a spindle 13 which is screwthreaded at H to work through a boss or nut I5 stationarily carried by the casing I, said spindle having a head It fitting loosely in an engaging neck or yoke H of the stator part 6. From Fig. 1 it will be apparent that the parts are in the position of maximum delivery capacity. If the stator 88 is displaced, that is raised, the landing block I will as shown in Fig. 5 recede from the rotor 4 and the gap between the rotor and the stator at its lower region will be reduced, the vanes ll however maintaining their same position or the positions in which their tips do not alter in rela-, tion to the circular portions of the landing block I and the stator part 6 with which they cooperate. The magnitude of the gap which is established between the rotor 4 and landing block I will determine the reduction in delivering capacity of the pump.v

The rotor in the example illustrated has five vanes II, each of which is shaped as shown in Fig. 2, being recessed at 18 so that with recesses 19 in the body 4 at the leading side of the vanes, fluid has access to the inner ends of the vanes, thus preventing variation in extension of the vanes afiecting volumetric discharge of the pump.

The reason for employing odd numbers of vanes will be apparent from a consideration of Fig. 5. Here it will be noted that the volumetric discharge to and from the delivery side of the pump, per increment of movement of the vane. when the axis of the rotor and stator are out of coincidence, is of a variable nature, as the width of the gap between the rotor and the stator is at a minimum when a vane is at either of the positions, marked (a). and at a maximum at the position marked b), while on the opposing side it is at a maximum at either of the positions marked .10) and a minimum at the position marked (d) Thus with odd numbers of vanes, when one vane is at the position (b) which equals the --,maximum width of the gap on this side, a vane "on the opposing side, as at (c), is in a position approaching maximum width on this side. It will then be readily seen that the volumetric fluctuations, due to varying width of the gap are practically of the same magnitude on either side of the rotor at any given moment, whereas with an even number of vanes the conditions would be reversed and there would be fluctuations in the discharge outlet from the pump varying from In Fig. 2 the parts 2| represent rubbing cheeks upon the stator cam plates 8 engaging the sides of the main casing l and serving to guide the stator and steady it when adjusted.

What I claim is:

1. In a rotary fluid pump embodying a stator member having internal work surfaces composing arc portions of two concentric cylinders of different radii and a rotor body therein having radial slidably projecting and retracting vanes working endwise against said surfaces, the improvement which consists in the provision of means operable exteriorly of the pump for adjustably moving the stator member in variable relation to the rotor body, between position limits of coaxialty of the two wherein the periphery of said rotor body contacts the arc portion ofsmaller radius of the stator member and a maximum eccentricity or non-coaxialty wherein said rotor body lies substantially equidistant between the parts of the stator member of different radii, so as thereby to vary the volumetric discharge of the pump. from full capacity to zero and vice versa.

2. In a rotary fluid pump embodying a stator member having internal worksurfaces composing arc portions of two concentric cylinders of different radii and a rotor body therein having radial slidably projecting and retracting vanes working'endwise against said surfaces, the improvement which consists in the provision of means operable exteriorly of the pump for adjustably moving the stator member in variable relation to the rotor body, between position limits of coaxialness of the two at which the pump has full discharge capacity and the maximum permissible displacement eccentrically from coaxialness at which the pump has zero dischargecapacity, so as thereby to vary the volumetric discharge of the pump anywhere from its full to its zero capacity.

3. The improvement in a rotary fluid pump according to claim 1, additionally including a main stationary casing inwhich the stator member is movable and wherein the rotor body is axially fixed.

4. The improvement in a rotary fluid pump according to claim 1, additionally including rollers carried by the radial vanes and cam or guide tracks for said rollers in the stator member by which said vanes are operated and maintained with their tips in contact with the work surfaces of said stator member.

5. The improvement in a rotary fluid pump according to claim 1, additionally including cut away portions in the leading faces of said radial vanes and cut away portions or enlargements opposite thereto in the receptive slide spaces therefor in the rotor body whereby the pumped fluid may have access to said spaces and get beneath said vanes.

6. The improvement in a rotary fluid pump according to claim 1, wherein the radial vanes carried by the rotor body are of an odd as well as a plural number.

7. The improvement in a rotary fluid pump according to claim 1, additionally including rollers carried by the radial vanes and cam or guide tracks for said rollers in thestator member by which said vanes are operated and maintained with their tips in contact with the Work surfaces of said stator member, together with relieving or counter-recessed grooves formed in said tracks coupling the adjacent spaces of such tracks.

RALPH JOHN SMITH. 

